Electroresponsive regulator.



L. L. TATUM.

ELECTRORESPONSAWE REGULATORi APPLlcAsou mio nov s. 19H.

Patented June 15, w15.

. regulation.

UNITED STATES PATENT OFFICE.

LEWIS/L. TATUM, OF MILWAUKEE, WISCONSINi ASSIGNOR TO THE CUTLER-HAMMER MFG. CO., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

ELECTRORESPONSIVE REGULATOR Specication of Letters Patent. Pateilted T1-111e 15, 1915,

Application led November 6, 1911. Sera1No.658,873.

To all relief/n it may concern.'

it known that I, Lewis L. TATUM, a citizen off; the United States, residing at Milwaukee, in the county of Milwaukee and .State of Wisconsin, have invented new and useful Improvements in Electroresponsive Regulators, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification;

My invention relates to improvements 1n electro responsive regulators.

It is one of the objects of myinvention to provide a positive and durable regulator by means of which a very fine degree of regulation may obtained.

Various other objects and advantages of my invention will be hereinafter clearly and fully set forth.

My invention. be used in various different relations for various different purposes.

For the purpose of illustration l have shown in the accompanying drawing one einbodiinent of my invention used for current lt should be understood however, that my invention is not limited to this particular application thereof or to the specilic form illustrated.

In the system selected for the purpose of illustration, the regulator controls the flow of current through an electrolytic bath contained in the schematically illustrated tank 1. Current is supplied to this tank from a generator 2 having an armature A and a shunt field winding F. It may be assumed that the current taken by the bath is sul- `iected to variation from any cause, as for example tl e sudden immersion in the bath. of material which increases or decreases the resistance of the circuit giving either a positive or negative current variation.

Such current i.. ations may be rectified in any preferred manner. ln the. system illustrated this is accomplished by a resistance 3 adapted to be cut in or out of the field circuit of the generator in accordance with the nature of the current variation. This resistance is connected to a series of contactsover which is adapted to move a contact arm 5. ln practice I prefer to have this arm actuated in a step by step manner. Any

` suitable operating mechanism may be employed. in practice. The mechanism illustrated is of a conventional form including a ratchet wheel 6 and two levers 7 and 8 each carrying a paw] 9 adapted to engage with said ratchet wheel. Pins 10 are provided to throw the pawls out of engagement with the ratchet wheel upon descent of the levers. The lever 7 moves the arm 5 in a clockwise direction and the lever 8 moves said arm in a counter-clockwise direction. The vlevers 7 and 8 are provided with operating solenoids 11 and 12 respectively, which solenoids are -provided with circuit making and breaking devices 13 and 14 respectively. The devices 1S and 14 are preferably of the type disclosed in my co-pending application Serial No. 658,872, filed Nov. 6, 1911. The devices 13 and 14 automatically make and break the circuits of their respective solenoids to cause the same to reciprocate theirplunger-s and thus imparta step by step movement to the rheostat arm 5. Furtheimore each of the devices 13 and. 14 breaks the circuit of its corresponding solenoid with a snap' action as clearly set forth in mycopending application aforesaid. The importance of this feature will be hereinafter set forth, The solenoids 11 and 12 are normally dee'nergized and are separately controlled by relays 15 and 1G respectively.

The relay 15 is adapted to respond upon a rise of current to cause the solenoid 11 to respond to operate the arm 5 to insert resistance in the field circuit of the generator. he relay 16 is adapted to Aoperate upon a decrease in current through the tank to cause the solenoid 1Q to respond to movethe arm 5 to out out resistance from the field circuit of the generator. The relay 15 comprises a solenoid having windings 17 and 18 provided with a. common plunger 19 to which is secured a switch 20' having coperating contacts lwhich it engages and bridges upon lifting of the plunger 19. The

winding 17 is connected in series with the tank 1 and is so designed as to respond to a predetern'iined rise in the current flowing through the tank. The winding'17 is the actuating winding for the switch Q0 and under normal current conditions has notL` sullicient strength to attract its plunger 19.

The relay 16 is provided with windings 21 and 22 having a common plunger 23 4to which is connected a switch 2l. The winding 21 which is the operating winding for the plunger 23 is so designed as to holdup its plunger under normal conditions, thereein :iid

hy holding the switch 24L out of engagement with its cooperating contacts and to drop its plunger upon a predetermined decrease in the llowof current through the tanl r1`he windings 18 and 22 of the relaysv have a double function. U nder certain conditions the windings 18 and 22 function to increase the pressure of the relay switches against their cooperating contacts to insure a good electrical contact. Under other conditions they have just the opposite effect, namely they tend to withdraw the relay switches from their stationary contacts, or in other words. restore the switch members to normal position. This latter function as will. loe hereinafter more clearly brought out greatly augments the sensitiveness oir' the relays and in consequence provides forv a very tine degree of regulation.

The reversal in function of the windings 18 and 22 is obtained by connecting said windings in parallel with the windings of solenoids 11 and 12 respectively.A The Soler noids 11 and 12 which are provided with relatively .larger magnetic frameslthan the relay solenoids producefupon interruption of their circuits hy the devices 13 and 1li-i, a hack discharge commonly known as an in,- ductive kick which sends av reverse current through the relay windings 18 and 22. rllhis reverses the polarity of the windings 18 and 22 resulting; in the reversal of function aforesaid.

l shallnow describe the operation ot' the regulator as a whole, at the same time more specilically bringing out the advantages thereof. Current flows from one terminal of the `eenerator armature by line 25 through the winding 21 of relay 16 thence through the tanli 1 and winding 17 of relay 15 to line 26 and thence to the opposite terminal of the generator. Assume now that the current flowing through the` tank falls below normal. yllhe winding 21 or rev lay 16" thereupon releases its plunger. The plunger 23 upon descending causes the relay switch 24: to bridge its contacts. This completes a circuit from line 25 by conductor 27 through the relay switch 24e hy conductor 28 and switch 1e, through the solenoid winding 12 and winding 22 or' relay 16 in parallel hy conductor 29 to line 26. Thus the solenoid 12 and winding 22 of relay 1G are energized The winding' 22 under these conditions opposes the winding 21 of relay '16Y thus tending to increase the pressure of the relay switcl 2ll against its coperatinp; contacts. This insures iii-in engagement or the relay contacts and eliminates the danger of arcinfj. The solenoid 12 operates to move the rheostat arm 5 in a direction to cut out the-resistance 3 from the field circuit of the generator, thereby tending to restore the current delivered to the tank to' normal value. The solenoid l2 will of course conf tinus to operate intermittently so lonal as the relay switch 24 remains closed. When however, the solenoid 12 has once responded its control switch 141-. will' open its circuit and also the circuit of the winding 22 ot relay 16. rllhe inductive kick of the solenoid 12 will then momentarily reverse the polarity of the winding 22 of relay 113., whereupon said winding will act cumulatively with the' winding?, 21 and tend to withdraw'the relay switch from its contacts. lt is a well known fact that a solenoid will release its plunger upon a lower current than will'suiice to cause it to litt its plunger. Thus ilE the relay 16 wasprovided with only the-winding; 21 and said winding: was adjusted to rele se i its plunger upon 'a small negative variation vin current, it would not-besul'liciently energined to attract its plunger until the current had been restored to a value above normaln 'lfhus with the relay equipped only with the winding 21it would be impossible to obtain regulation of current within close li .c s. The winding 22 however, counteracts'the aforesaid condition. y proper design and proportion oi the solenoid 12 andthe relay solenoid the eiiieet of the inductive lriclrot" the former upon the winding,i 22 may he so calculated as to more than counterhalance the additional pull required to open the rclay switch 16. Under such conditions the relay could loe made to resume normal position upon each stroke of the solenoid 12 or at least within a 'predetermined limit ofcurrent vari ation. Hence the relay may he adjusted to drop upon a very small negative variation in current and yet he insured restoration to normal position without an un- .fduly 'large increase in current. @t course under some conditions the current variation might he so wide that the cumulative eil'ect of the windings 21 and 22 would not he suilicient to restorel the relay to normal position, hut under such circumstances with the steps of resistance regulation properly cal culated this would oe advantageous rather than disadvantageous. The result would los that so long; as the current varifiition ei:- ceeded a predetermined limitv the relay would remain closed during? a nrunlier of strokes of the solenoid 12witlithe result `thatthe solenoid 12 would so operate the regulator as to quickly brins; the current within the limit at which the cumulative effect of the windings 21 and 22 would raise the relay plunger and open the switch 24. Thereafter until current had been restored to approximately normal value the relay 16 would vibrate. thereby necessitatin/e a cour plete cycle of operationv ol the r lay and .solenoid 12 as prerequisite to eaci step of vresistance regulation.

down the operation of the regulator as a whole as normal current conditions were preached, and in consequence permit resto# ration of normal current conditions with a iine degree of accuracy. n l

To recapitulate, the Winding 22 upon operation oi the relay responds to oppose the winding 2l and thus insure a goed electrlcal contactof the. relay switch and upon interrupl tion of circuit by switch 141i receives the inductive kick of the solenoid 12 causing its polarity to change and causing it .to act cuinulatively with the winding :Z1 to restore the relay switch to normal position. This :hangs in polarity of the winding Q2 is n'iefreY momentary, said winding becoming inert with cessation or' the baclr discharge of solenoid i2 which is of very short duration. This temporary period of reverse polarity of the winding is however amply suilicient to enable said winding to perform its desired function and yet is of suchshort duration to in no wise eiect ordelay subsequent operation of the relay.v The purpose of providing ior a snap action of the switch 14 is for the purpose-of securing the full effect of the bach discharge of the solenoid 12 upon the relay windinf.r 22. Should the operation f switch ll be slow the baci; discharge of solenoid i2 might take the path including said switch instead of that including relay winding Assume non` that there is a positive variation 'of current or in other words en abnormal rise of current, The rclay 15 responds, closing the circuit of ratcheting solenoid 11. This circuit extends from line 25 by conductor 39, relay switch 20 and switch 13 through solenoid winding 11 and relay winding 18 in parallel by conductors 31 and 29 to line 2.6. This causes operation of the rheostat to insert resistance in the field circuit of the generator and in consequence a reduction in the current supplied to tank 1.

The winding 18 of relay performs the same functions as the winding 22 of relay 15. This winding howeverf instead of normally opposing the main relay winding noi`- inally ciunulatively therewith and opn poses the main winding when energized by inductive licl. ci' solenoid 11. This dif- =rnce in relation of the windings of the y lil necessary in View of the character oi said relay. lnlilre relay 1G its plunger is normal down. and it responds to raise its plunger only upon an increased flow of current t rough the winding 17.` lWith a. small increase of current it is obvious that the pull on the plunger by the winding 17 would be weak. However, with the assistance of the winding 18 the relay 15 will raise its plunger with the requisite -`amount of force .to-insure good electrical contact 0f its switch upon a small rise in current. Likewise the relay l5 if only'provided with the coil 17 would tend to hold the. switchl() in closed position until the current had been reduced to a degree considerably below that at which the windingvl Wasacljustedtouespend. However with the provision of the coil 18 which upon opening of the switch 13 opposes or bucks the coil 17 the release of the relay may be insured under any desired current conditions or at least within certain limits as previously explained. The operation of the relay 15 upon an abnormal rise in current is substantially the same as that of the relay `16 upon an abnormal decrease in current, and accordingly it will be unnecessary to explain the operation of the relay 15 in detail. Upon an abnormalrise in current within a prescribed limit it would vibrate until the rheostat had been operated to restore the current to approximately normal value. If on the other hand the variation in current was wide it would respond and remain closed until the rheostat had been operated to reduce the current within a certain limit and would thereafter 'vibrate until-the value of current had been restored to the desired degree. The relay 16 providing means whereby the .flow of currentlnayA be restored with ay fine degree of accuracy from negative variations and the realy 15 providing means whereby the current may be restored with a fine degree of accuracy from positive varia tions it naturally follows that the two relays would confine the variations in current between very narrow limits thereby providing a mostsatisfactory regulation.

What I claim as newiand .desire to secure by Letters Patent is as follows:-

1. In a regulator, in combination, an electro-responsive device operating automatically under certain electrical conditions, and means associated with said device and acting upon the aforesaid operation thereof to first tend, to effect continued movement of the same and then tend to effect return move` ment thereof.

2. In a regulator, in combination, an elec tro-responsive device loperating automatically under certain electrical conditions, and normally inert electro-responsive means sociated therewith and acting upon the aforesaid operation thereof to lirst tend to effect continued operation in the same direction and then tend to effect return` movement thereof.

3. In a regulator, in combination, an electr0-responsivc relay, and means associated with said relay to assist in eli'ecting movement thereof away from andA toward normal position. progressively, said means being effective for only a temporary period where` by the sensitiveness of said relay is rendered independent thereof.

4. In a regulator, in combination, an elec` tro-responsive relay, and normally inert electro-responsive means associated. therewith to assist and oppose its windin in a predetermined cycle of operation ot said relay. A

5. In a regulatonin combination, an elecici f means Wi ndmgs isha Windi errang being wsponsi to the back dscal'g@ of said Soenod wning iorl'etum tQ Befund 'positm n mness whereof, have hereunto sub scribed mv name in thepiesence zal" twg Wit- .ness/a LJWIS L. TA'UM.

FRANK Ha HUBBMRD, Gu W. Hjnms,

said y 

